1. Field of the Invention
The present invention relates to an electrode assembly for a rechargeable battery, a rechargeable battery using the electrode assembly, and a fabricating method thereof. More particularly, the present invention relates to an electrode assembly for a rechargeable battery, which may prevent the electrode assembly from moving in a battery housing, e.g., a can, by not allowing the electrode assembly to unfasten when an external impact is applied.
2. Description of the Related Art
In general, as portable electronic apparatuses, e.g., video cameras, mobile phones, portable computers, etc., have continued to progress and become more light weight with increased high technology content, extensive research in the field of rechargeable batteries used as power sources has been made. Rechargeable batteries may include, e.g., a nickel-cadmium batteries, a nickel-metal hydride batteries, a nickel-zinc batteries, lithium rechargeable batteries, etc. Among these types of batteries, the lithium rechargeable batteries, which may be made in a small size with a high capacity, have come into widespread use in the field of high-tech electronics due to advantages which may include high operation voltage and high energy density per unit weight.
An electrode assembly in a can, i.e., a container, may transform or rotate when an external impact, e.g., from a dropped battery, is applied to the lithium rechargeable battery. Lithium rechargeable batteries which are being used for electric tools may possibly have the upper part and the lower part of the electrode assembly transform or deteriorate from vibrations transferred to the lithium rechargeable battery when the electric tool is operating.
Workers may also handle electric tools carelessly, and the possibility of electrode assembly damage may thus increase. Transformation or dislocation of the upper and lower part of the electrode assembly may generate a short circuit, and the increased internal resistance may cause a problem by generating heat.
One safety test for a battery is a drum test for determining whether an electrode assembly is transformed, dislocated or rotated by measuring the internal resistance, after the battery is moved up, down, right and left in the octagon-shaped drum. When the battery undergoes the drum test, the electrode assembly is moved up and down, and the welded region of an electrode tab may be deintercalated, thereby substantially increasing internal resistance. As a result, there is a need for new battery electrode technologies that address and overcome the problems and shortcomings of prior art batteries.